The vast growth in electronics and in data processing is making it increasingly necessary for DC power supplies (AC to DC converters with filters and possibly feedback regulating circuits) to be mass produced in large numbers. For customer satisfaction, the manufacturers of such power supplies must sell power supplies which are guaranteed to work. The same is true for constructors of data processing systems who employ the power supplies in their systems. These data processing power supplies are either purchased directly from a special manufacturer or are produced by the constructor himself. In either case the power supplies must be subjected to rigorous tests to ensure that the system which they supply operates satisfactorily. In the present state of the art with which we are familiar, testing equipment does not combine both speed and the ability to handle the large number of tests which are made on the power supplies. In fact, all previous checking equipment of which we are aware requires a large number of manual actions on the part of a technician in charge of testing a particular supply.
The prior art equipment generally includes a measuring unit which allows measurement to be made, on the one hand, of the various levels of AC current activating the DC power supply and, on the other hand, of the voltage levels which appear at the terminals of a load connected to output terminals of the power supply to be tested. Each time that the technician wishes to check the input and output levels under different operating conditions he has to perform manual actions which involve:
1. Adjusting a measuring unit, which consists chiefly of a voltmeter for measuring the input and output voltages of the power supply; and
2. Altering the level of the AC input voltage and the value of the impedance of a load arranged across the output terminals of the power supply. Each of the values read from the measuring unit must, moreover, be noted with a pencil and paper or the like, so that they can either be entered on a log sheet which accompanies the power supply and relates to the operating tests, or to enable a fault-finder to locate a fault when the values measured at the output from the power supply are not what they should be in normal operation, for given AC input currents.
An object of the present invention is to provide new and improved apparatus for high speed checking of power supplies before use or delivery. Another object is to provide an apparatus for improving the standard of tests made on power supplies by eliminating all manual operations while the measurements are being made, while increasing the number of checks by automating the measurement process.